As mentioned above you should think of moving to the Vijayangar area. The land price in this area is appreciating because of the proximity to the IT companies. The area is well connected as the outer ring road and Hunsur road is very near the area. Most of the sites are approved by the Mysore Urban Development Authority (MUDA), so you should not have any hassles when it comes to purchasing the property.
If you are moving away from Bangalore because of the pollution and traffic, then you should not move to any of the areas suggested above. These areas may not have the traffic the Bangalore faces, but there is much more traffic here than other parts of Mysore. But, if you are moving to Mysore to live in an environment where the air is fresher, you should try out other areas of Mysore like Vijayanagar IV stage or projects near Bogadi Road. These areas around eight kilometres from Mysore railway station, and are much quieter than the hustle and bustle of the main part of the city. You can buy land in these areas for around Rs. 2000 per sq.ft.
You have made a good choice of moving to Mysore. Many people are moving from Bangalore to Mysore because of the old world charm that Mysore offers, and the overpopulation in Bangalore. You should look at areas like Jayalakshmipuram, Gokulam, and Yadavgiri. These areas are centrally located, and have many malls, hospitals, and schools. You can travel to other parts of the city using buses or autorickshaws. Jayalakshmipuram has educational institutions like Chinmaya Vidyalaya, Mahajana College, and SBRR Mahajana College. Gokulam is another very good locality which is well connected by the KRS Road. You can buy a property in Gokulam for around Rs. 4600 per sq.ft.